Bifurcation occurs when a vessel (or main branch) splits into two separate blood vessels (or side branches). Typically, the two side branches are smaller than the main branch. In the case of blood vessels, plaque buildup in the bifurcated region may cause stenosis or otherwise compromise blood flow. These types of lesions may occur within the main branch as well as in the side branches.
Over the years, a few techniques have been developed to attempt to treat lesions at bifurcations. An example of a bifurcation stent delivery device is described in U.S. Patent Application Publication No. 2005/0209673 (Shaked). Specifically, Shaked's device uses an additional lumen to accommodate a secondary guide wire that is inserted into a side branch at a bifurcation. The inventor hereof has recognized, however, that the exit point for the secondary guide wire occurs at the midpoint of the device. As a result, the struts from the exit point may get incorrectly aligned, which may hinder the deployment of a side branch stent.
Another bifurcation device is disclosed in U.S. Pat. No. 7,686,845 (Sequin). Sequin's device uses a self-expanding stent, which the inventor hereof has also recognized tends to be difficult to maneuver and deploy, especially if the plaque burden in the vessel is high. Moreover, the struts of Sequin's stent are subject to grabbing on to plaque during deployment, which may result in inaccurate placement of the stent, damage to the vessel, plaque shift, dissection, or even plaque embolization.